A harmonic oscillator, also called as a dielectric resonator, is high in dielectric constant and low in electromagnetic loss, and thus is widely used in various microwave radio frequency devices such as filters, duplexers, and the like. In general, the harmonic oscillator is cylindrical and is formed by integrally sintering the microwave dielectric ceramics. In a resonant cavity of a microwave device such as a filter, a duplexer and the like, a support base is generally arranged at the bottom of the harmonic oscillator and fixed with respect to the resonant cavity. In order to fix the harmonic oscillator, the harmonic oscillator is directly attached to the surface of the support base in general.
In addition, although the microwave dielectric ceramic is high in dielectric constant, low in electromagnetic loss and high tolerance power and the like and conforms to the requirement of the harmonic oscillator, the miniaturization demand of the filter and the duplexer of the people is further increasing with the technological development, the continuous improvement of the product integration. In the related art, the size of the cavity filter or the dubplex is inversely proportional to a resonant frequency. If the size of the resonant cavity is directly reduced, the corresponding resonant frequency is increased, as a result, the filtering function of the filter may not be met. At present, the problem to be urgently solved by the research staffs commonly is about how to realize miniaturization without affecting the normal using function of the cavity filter and the duplexer.